Why is my HTC One M8 lagging after Lollipop 5.0 update?

Ever since i updated to the new software yesterday my phone has been lagging when i open up messages but especially using the keyboard, i can basically write an entire message out before it shows and the haptic feedback kicks in.. its ridiculous.
I've power cycled, cleaned it (clean master) and its still doing it..
i don't have a lot on this phone as it is, im using 11% of my storage, i have about 20 photos, no music or videos, i keep running apps to a minimum... any advice, or at least anyone having the same issue?

You probably do NOT need to do this. Just try a simple power off (all the way off, not the close and reboot), then reboot.

Always try the simple method first, because if it was common to require a cache clear HTC would have built it into the update.

You are going from one base to another not just a update of the same base. For one its going from using Dalvik to using ART and thats a big change. wiping the cache is simple and he won't lose any data , he might need to reinstall some apps from the playstore. I do agree to try the complete shutdown but if by chance a old system file has been left behind a good wipe can;t hurt either.

You are going from one base to another not just a update of the same base. For one its going from using Dalvik to using ART and thats a big change. wiping the cache is simple and he won't lose any data , he might need to reinstall some apps from the playstore. I do agree to try the complete shutdown but if by chance a old system file has been left behind a good wipe can;t hurt either.

Using the Facebook messenger app, I came across an issue where when I sent a message on my HTC One M8 running stock android 5.0.1 with sense 6 unlocked, it would sometimes freeze for around 10 seconds, locking up both the app and most of the functionality of my phone.
Since I've had this issue and have been able to replicate it after using HTC's tool to reinstall my OS and only the messenger app, I figure other people will as well.
Sorry for the keywords, trying to make this google-able on the chance other people have this issue with their HTC One M8 on lollipop unlocked or developer edition phone using the Facebook messenger app.
The issue seems to come from the in-app sounds. When my phone is on silent or vibrate, I can send messages without the hang or lag, but as soon as I turn the ringtone volume up passed muted, it starts to go really slow again.
My solution to this is to go into the fb messenger app settings, and uncheck the box that says "in-app sounds".
I have sent multiple reports of the bug to Facebook, so hopefully it'll be patched soon enough.

I have an issue with my HTC ONE M8 which came about after the update to Android 5.0. The issue is that my phone vibrates when notification come. Sounds normal isnt it. Well the real issue is that it keeps on vibrating ever 15-20 sec till the time I see the notification. It is really irritating. I have deleted all the third party apps which might be creating any issue, switched off the vibration mode as well as when I run my phone on the silent mode still it vibrates. Please help me with this issue

I have an issue with my HTC ONE M8 which came about after the update to Android 5.0. The issue is that my phone vibrates when notification come. Sounds normal isnt it. Well the real issue is that it keeps on vibrating ever 15-20 sec till the time I see the notification. It is really irritating. I have deleted all the third party apps which might be creating any issue, switched off the vibration mode as well as when I run my phone on the silent mode still it vibrates. Please help me with this issue

I have an issue with my HTC ONE M8 which came about after the update to Android 5.0. The issue is that my phone vibrates when notification come. Sounds normal isnt it. Well the real issue is that it keeps on vibrating ever 15-20 sec till the time I see the notification. It is really irritating. I have deleted all the third party apps which might be creating any issue, switched off the vibration mode as well as when I run my phone on the silent mode still it vibrates. Please help me with this issue

Go to settings - accessibility - notification reminder, and set it to off.

Factory resets should be done before and/or after any major OS update. This is even more true for the Lollipop update since it is completely overhauling the app runtime (moving from Dalvik to ART). I bet this would take care of a lot of the issues people are having.

I've been having similar problems since updating to lollipop 5.0.1.
I've tried rebooting, factory resetting, wiping the cache, deleting apps; the whole lot, and it hasnt helped. I'm super stuck, and relatively new to android having just switched from iPhones.
Any suggestions?

I've been having similar problems since updating to lollipop 5.0.1.
I've tried rebooting, factory resetting, wiping the cache, deleting apps; the whole lot, and it hasnt helped. I'm super stuck, and relatively new to android having just switched from iPhones.
Any suggestions?

Thanks in advance

Did you read the full thread before replying?

Turn off notification sound in Facebook?
Uninstall Facebook for s day to see if that helps?

If you follow the thread carefully you will see that most people traced the lag to Facebook.